No difference in expression levels of the prostaglandin synthesis enzyme Cyclooxygenase2 (Cox2) was found between Abcb4+/+ and Abcb4−/− mice (data not shown), suggesting that reduction of the inflammatory process is not the mechanism responsible for the protection against colon cancer observed in Abcb4−/− mice. The gene discussed is ABCB4; the disease is colonic neoplasm.